Of course this is not strictly speaking a focaccia.
Preheat an oven to 230c.
Brush a swiss roll tin or baking tray generously with olive oil.
Sieve the plain flour and the bread soda into a big bowl.
Add the salt, the 50g of grated cheese and mix with your hands.
Make a well in the centre, pour in most of the buttermilk, and with one hand stiff and your fingers spread out like a claw, start mixing in a full circle once the butter milk has gone in.
Keep mixing like this until you have a soft dough
Do not knead it but work it very gently to bring it together.
Transfer to a floured surface and roll it out to about 35x20cms (14x8inches), and transfer it to the oiled tray.
Brush the top with some more oil and sprinkle with the 75g(3oz) grated cheese
Put it in the oven and cook for 18-25 mins, depending on how thick it is.
Turn the oven down to 200c after 10 mins.
When cooked, it should feel firm in the centre and be gorgeous and golden brown.
Transfer it to a wire rack and cool for a couple of mins, then cut it into squares and serve!!
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